Lung cancer accounts for over 160,000 deaths per year in the U.S., more than breast, colon, prostate and pancreatic cancer combined. The overall five-year survival rate for lung cancer is approximately 15%, and unlike other solid tumors, such as colon or breast cancer, little progress has been made in improving survival. Early-stage non-small cell lung cancer (NSCLC) is primarily treated by surgical resection. Unfortunately, after resection, one-third to one-half of early-stage patients will die of metastatic recurrence. Adjuvant chemotherapy (ACT) improves the survival of patients with early-stage disease and has become the standard treatment for patients with resected stage II-III NSCLC. However, the five-year survival advantage of ACT is only 4%-15% suggesting that many patients do not benefit. Management of early stage lung cancer following surgical resection still relies on metrics such as tumor size and lymph node status to guide decision making regarding adjuvant chemotherapy (ACT). Given the morbidity associated with ACT, it is imperative to develop new prognostic tools to identify those patients with high probability of relapse.